@@HowRadiologyWorks Anyway, just have one question. When it comes to 3D reconstruction, are we gonna use the same approach (spreading evenly but in 3D rotation)?
@@binhnq_tokyo_shorts_24 yes we follow the opposite of the path of the x-rays during acquisition. So all pointed from the detector cells to the focal spot. In modern scanners this is a cone shape so it is called cone-beam CT
Your explanation is beautiful, thank you. But I have a question, is it required to be FBP after the Back projection?I mean, filtering it once or twice, before and after the Back projection Please answer as soon as possible sir ❤
Also my college camp have more than 10k students im spread your channel in the Whatsapp group of the colleges which have many hundreds once i get permission
Simple and easy. Great work Dr Brian Question? Is FBP still the main method used in reconstruction today or it it substituded by Iterative reconstruction ?
We have another video on iterative reconstruction which you may have encountered. FBP is typically used as the first guess for iterative CT so it is still important.
Hi sir ...you explained the back projection practically...why u don't explained the filter back projection practically ..I need practical explanation of filter back projection sir..thank you.
Thanks Kandavel, I can work on it. Luckily the backprojection part is the same so I think you are just asking for a more practical description of the filtering process right?
My question is how the machine figure out the voxel attenuation coefficient since its just add them all together along the line path or line integral idk I maybe mistaken for the name so how the machine figure out these pixels values
The FBP algorithm is one way to figure out the attenuation values from the line integrals. Also iterative reconstruction is another method. These methods are called image reconstruction and take many views of line integrals to perform the reconstruction.
Peator the line integral is just a fancy way of saying add up the voxel values along a line. When we take an X-ray image this part is done automatically. Then we need to find the values for the image voxels. So the FBP converts the data to images
@@HowRadiologyWorks so how many photons or line integral pass per square cm or mm Also what if pixel size is 1mm and within this 1mm there is many or two different attenuation structure like small calcification smaller than micrometer and air what ct number is assigned to it the average but how they gonna count the attenuation cofe I tried to add the voxels values like from above and 45 degree and right but some lines pass between these two different square values Srry if im confusing u im newbie
you need to improve sound in your videos, you are missing out with the great content, trust me. Not sure if it's your mic or the way the audio quality is reduced or compressed but you need to listen and compare that to other videos, it will get you much more views through increased comfort reduced drop out feeding youtube algorithm what it wants.
One of best channels regarding radiology over the internet im very thankful to find ur channel
Thanks for the words of support, these comments help me know I’m on the right track.
God bless you for this explanation
No problem
Thank you so much sir and hats off for your dedication and love to provide us with the best 💖
You’re welcome. Thanks for dropping the comment.
Finally a plain English explanation of FBP. Thanks!
Glad it was helpful Erik☺️
Incredibly superb ! What an euro imagination. Gr8 Way of teaching
Thanks Dark Horse, please share with your friends and coworkers
Also check out our channel for other videos especially the one on iterative recon
@@TheNettforce
👍
finally after a year course of radiology i got it, thank you so much
You’re welcome, glad you liked it
Thanks a bunch, you really made it easy for me to understand the topic :)
Glad to hear that! Thanks for the comment
Best explanation I've found so far.
Thanks a lot of bro!
Thanks, really appreciate it.
@@HowRadiologyWorks Anyway, just have one question. When it comes to 3D reconstruction, are we gonna use the same approach (spreading evenly but in 3D rotation)?
@@binhnq_tokyo_shorts_24 yes we follow the opposite of the path of the x-rays during acquisition. So all pointed from the detector cells to the focal spot. In modern scanners this is a cone shape so it is called cone-beam CT
Highly valuable content. Thanks from a radiology resident
Glad it was helpful! Thanks Rad Resident. Where about in the world are you?
@@HowRadiologyWorks Hey. I'm located in Algeria
Again helping the new generation with some key concepts! Thx doc big hugs from Italy ❤️🔥☢️
Thanks for teaching the next generation 😀
thank you for the concept it was really helpful
Glad to hear that! Thanks for the comments, they are the fuel for me.
Had difficulty understanding the FBP concept but thankfully I came across your video! Helped a lot in visualising how FBP works, thank you!😃
You’re welcome. We have separate videos on the filter and back-projection too if you need more details.
That was very understandable. Thanks, and i subscribed
Awesome, thank you! Share the Rad Love with your colleagues
amazing dude, what a wonderfull concept you have given to me
You’re welcome Harsh
A good video, thanks!
Thanks jicheng.
Your explanation is beautiful, thank you. But I have a question, is it required to be FBP after the Back projection?I mean, filtering it once or twice, before and after the Back projection
Please answer as soon as possible sir ❤
Ali the Filter is just done once before the backprojection
@@HowRadiologyWorks Thanks 🌹
Also my college camp have more than 10k students im spread your channel in the Whatsapp group of the colleges which have many hundreds once i get permission
Yea please pass along this channel to others at your college
Simple and easy. Great work Dr Brian
Question?
Is FBP still the main method used in reconstruction today or it it substituded by Iterative reconstruction ?
We have another video on iterative reconstruction which you may have encountered. FBP is typically used as the first guess for iterative CT so it is still important.
@@HowRadiologyWorks yea u think i have seen it. I will revise the channel. Thanks a lot for your response.
Hi sir ...you explained the back projection practically...why u don't explained the filter back projection practically ..I need practical explanation of filter back projection sir..thank you.
Thanks Kandavel, I can work on it. Luckily the backprojection part is the same so I think you are just asking for a more practical description of the filtering process right?
@@HowRadiologyWorks yes sir ,thank you
My question is how the machine figure out the voxel attenuation coefficient since its just add them all together along the line path or line integral idk I maybe mistaken for the name so how the machine figure out these pixels values
The FBP algorithm is one way to figure out the attenuation values from the line integrals. Also iterative reconstruction is another method. These methods are called image reconstruction and take many views of line integrals to perform the reconstruction.
@@HowRadiologyWorks so do i need to study calculus to understand how to get these squares value because I cannot conceptually its so hard
Peator the line integral is just a fancy way of saying add up the voxel values along a line. When we take an X-ray image this part is done automatically. Then we need to find the values for the image voxels. So the FBP converts the data to images
@@HowRadiologyWorks so how many photons or line integral pass per square cm or mm
Also what if pixel size is 1mm and within this 1mm there is many or two different attenuation structure like small calcification smaller than micrometer and air what ct number is assigned to it the average but how they gonna count the attenuation cofe
I tried to add the voxels values like from above and 45 degree and right but some lines pass between these two different square values
Srry if im confusing u im newbie
Peator a few questions here:
1) depending on the dose there are usually something like 10,000 X-ray photons per detector
We back project the image from sinogram or raw data ??
The raw data is corrected by what we call calibrations. It is still in the sinogram space, it is filtered along rows and then backprojected
@@TheNettforce thanks sir !
How can I donate to support your channel
Peator please continue to like, comment and share. I don’t have a donate mechanism setup yet.
you need to improve sound in your videos, you are missing out with the great content, trust me. Not sure if it's your mic or the way the audio quality is reduced or compressed but you need to listen and compare that to other videos, it will get you much more views through increased comfort reduced drop out feeding youtube algorithm what it wants.
Thanks Nauka for the constructive feedback, I will try to improve the audio more over time
Too slow!, awith annoying background music.
Thanks for your feedback.